Recently, interest in solid state disks is greatly increasing. A solid state disk uses a flash memory, a Synchronous Dynamic Random Access Memory (SDRAM) and the like, instead of a hard disk drive.
Accordingly, since a mechanical driving device such as a motor used for a hard disk drive is not required in the solid state disk, the solid state disk may be operated without almost generating heat and noise. In addition, the solid state disk may be robust to external shocks, and may achieve a high data transmission rate, compared to the hard disk drive.
A solid state disk is broadly classified into a flash-based Solid State Disk (SSD), and a Dynamic Random Access Memory (DRAM)-based SSD, and the like. The DRAM-based SSD may support quick reading and writing, and may have relatively strong durability. The flash-based SSD may have properties such as non-volatility, economical efficiency, low-power consumption, and the like.
In a solid state disk, data is written on a plurality of memories via a plurality of channels that are independent of each other, and the data is read from the plurality of memories. For example, the plurality of memories may be connected to 4 channels, 8 channels, or 16 channels that are independent of each other. Here, a plurality of channels may be driven by a plurality of output pads or a plurality of input pads. However, when the plurality of output pads or the plurality of input pads are simultaneously enabled, ground bouncing may occur, and a power required by pads may be increased. Accordingly, there is a need for a technology that may properly control signals provided to a plurality of output pads or a plurality of input pads.